WOOL - From Sheep to Spun Yarn:
There are 6 steps involved in making wool yarns; shearing, skirting, washing, carding, spinning and dyeing. Shearing can be done one of two ways; either with hand shears, or using power shears. Professional shearers can shear an entire sheep in less than one minute, without even scratching the sheep. When shearing, the fleece is usually removed in a single piece. Once the fleece has been removed from the sheep, the next step is to skirt and card it.
Skirting is the process of removing unusable or extremely soiled bits of wool from the fleece, before processing. With animals such as sheep, the fleeces contain a lot of lanolin, which is either removed or left in the fleece, depending on how the fleece is to be used. If the finished yarn is meant to be water-repellent, then the lanolin will not be removed. Once the fleece has been skirted, it is carefully washed to remove extraneous vegetable matter, twigs, straw, etc. and lanolin if its to be removed. The washing process may be done with large washing machines or by hand and can be very time consuming. Much care has to be taken when washing fleeces, because too much agitation can result in undesired felting.
A sheep shearer uses a supporting back sling while shearing sheep
After the fleeces have been cleaned and dried, they may be spun immediately, but they are usually carded first. Carding is the process of combing the fibers into fine straight layers, so that they can be easily spun. Once the fibers have been spun, they are referred to as either a rolag (if handcarded) or roving (if machine carded).
At this point, the fibers are prepared for spinning. They may be handspun using a spindle or spinning wheel or machine spun. After spinning, the yarn will be dyed and rolled for packaging. The wool fiber may also be sold for spinners after cleaning and carding or as roving, both for spinning and for big-needle knitting and thrumming.
COTTON - From Boll to Ball:
Because cotton is a plant fiber, the process used is slightly different than for animal fibers.
Cotton is a soft, fluffy fiber, which grows in a boll (a protective shell around the fiber) around the seeds of cotton plants. Cotton is grown world wide, especially in tropical and subtropical regions, such as Mexico, Australia and Africa. It has been used for thousands of years and is separated into several categories. Egyptian Cotton is generally considered one of the best, however few 'Egyptian Cottons' are truly from Egypt.
After harvesting, the cotton fiber, which is attached to the seeds is placed in a cotton gin. The gin separates the seeds and other residue (grass, leaves, dirt, etc.) from the fiber.
There are several types of gins. Saw Gins are circular and grab the fiber, pulling it through a narrow grating, too small for the seeds to pass through. Roller Gins, which are used for longer staple cottons, run the cotton over a leather roller attached to a blade, which detaches the seeds.
Once the cotton has been ginned, it is referred to as lint and is compressed into bales, which are then sent off to be carded, spun and dyed.
A woman spins yarn in Nepal
An antique cotton gin on display
Armenian women harvest cotton
*Bamboo yarns, by the strictest definition, are not natural since the bamboo is chemically processed in order to turn it into yarn. The process is actually similar to the process of making soap, where strong solutions of sodium hydroxide are used to change fat into soap. The other chemical used is carbon disulfide, an organic solvent that evaporates very quickly. In large concentrations it is a toxin. However, because it evaporates so quickly, it does not remain in the fibers. It also breaks down once released, in a few days, to simpler carbon and sulfur compounds which are all around us in daily life. The end product is very clean, non-toxic and actually very eco-friendly and biodegradable. Unlike synthetic yarns or fabrics, bamboo fibers will decompose in soil in a short time.
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